Global coral bleaching event detection from satellite monitoring of extreme heat stress

Over the past four decades, coral bleaching events have occurred with increasing frequency and severity, directly linked to increasing ocean temperature due to climate change. For the latter half of that period, satellite monitoring by NOAA Coral Reef Watch in near real-time has provided invaluable insight into bleaching risk. Here, we describe a novel application of those products to develop basin-scale tools for tracking the development of extreme heat events that enable monitoring of global coral bleaching events. Case studies of historical extreme events (1982-2018) across the three tropical ocean basins (Indian, Pacific and Atlantic) were analysed using this basin-scale approach to identify key thresholds of heat stress extent for the definition of global bleaching. Global-scale events are apparent when all three tropical basins experience heat stress in at least 10% of reef-containing locations. An 8-month ‘detection window’ was determined as the optimal period of time through which pixels exposed to heat stress should continue to be counted as part of a basin-scale event to account for seasonal variations across ocean basins. Understanding the broader context of basin-scale conditions can inform management of individual reefs, management networks and other reef stakeholders. Operationalising this product for near real-time delivery will provide an effective communication of the status of coral reefs around the world during an era of unprecedented climate threats

Subretinal Implantation of Electrospun, Short Nanowire, and Smooth Poly(ε-caprolactone) Scaffolds to the Subretinal Space of Porcine Eyes

Biodegradable scaffolds play an important adjunct role in transplantation of retinal progenitor cells (RPCs) to the subretinal space. Poly(ε-Caprolactone) (PCL) scaffolds with different modifications were subretinally implanted in 28 porcine eyes and evaluated by multifocal electroretinography (mfERG) and histology after 6 weeks of observation. PCL Short Nanowire, PCL Electrospun, and PCL Smooth scaffolds were well tolerated in the subretinal space in pigs and caused no inflammation and limited tissue disruption. PCL Short Nanowire had an average rate of preserved overlying outer retina 17% higher than PCL Electrospun and 25% higher than PCL Smooth. Furthermore, PCL Short Nanowire was found to have the most suitable degree of stiffness for surgical delivery to the subretinal space. The membrane-induced photoreceptor damage could be shown on mfERG, but the reductions in P1 amplitude were only significant for the PCL Smooth. We conclude that of the tested scaffolds, PCL Short Nanowire is the best candidate for subretinal implantation

Optimal spatiotemporal scales to aggregate satellite ocean color data for nearshore reefs and tropical coastal waters: two case studies

Remotely sensed ocean color data are useful for monitoring water quality in coastal environments. However, moderate resolution (hundreds of meters to a few kilometers) satellite data are underutilized in these environments because of frequent data gaps from cloud cover and algorithm complexities in shallow waters. Aggregating satellite data over larger space and time scales is a common method to reduce data gaps and generate a more complete time series, but potentially smooths out the small-scale, episodic changes in water quality that can have ecological influences. By comparing aggregated satellite estimates of Kd(490) with related in-water measurements, we can understand the extent to which aggregation methods are viable for filling gaps while being able to characterize ecologically relevant water quality conditions. In this study, we tested a combination of six spatial and seven temporal scales for aggregating data from the VIIRS instrument at several coral reef locations in Maui, Hawai‘i and Puerto Rico and compared these with in situ measurements of Kd(490) and turbidity. In Maui, we found that the median value of a 5-pixels, 7-days spatiotemporal cube of satellite data yielded a robust result capable of differentiating observations across small space and time domains and had the best correlation among spatiotemporal cubes when compared with in situ Kd(490) across 11 nearshore sites (R2 = 0.84). We also found long-term averages (i.e., chronic condition) of VIIRS data using this aggregation method follow a similar spatial pattern to onshore turbidity measurements along the Maui coast over a three-year period. In Puerto Rico, we found that the median of a 13-pixels, 13-days spatiotemporal cube of satellite data yielded the best overall result with an R2 = 0.54 when compared with in situ Kd(490) measurements for one nearshore site with measurement dates spanning 2016–2019. As spatiotemporal cubes of different dimensions yielded optimum results in the two locations, we recommend local analysis of spatial and temporal optima when applying this technique elsewhere. The use of satellite data and in situ water quality measurements provide complementary information, each enhancing understanding of the issues affecting coastal ecosystems, including coral reefs, and the success of management efforts

Olive phenology as a sensitive indicator of future climatic warming in the Mediterranean

Experimental and modelling work suggests a strong dependence of olive flowering date on spring temperatures. Since airborne pollen concentrations reflect the flowering phenology of olive populations within a radius of 50 km, they may be a sensitive regional indicator of climatic warming. We assessed this potential sensitivity with phenology models fitted to flowering dates inferred from maximum airborne pollen data. Of four models tested, a thermal time model gave the best fit for Montpellier, France, and was the most effective at the regional scale, providing reasonable predictions for 10 sites in the western Mediterranean. This model was forced with replicated future temperature simulations for the western Mediterranean from a coupled ocean-atmosphere general circulation model (GCM). The GCM temperatures rose by 4·5 °C between 1990 and 2099 with a 1% per year increase in greenhouse gases, and modelled flowering date advanced at a rate of 6·2 d per °C. The results indicated that this long-term regional trend in phenology might be statistically significant as early as 2030, but with marked spatial variation in magnitude, with the calculated flowering date between the 1990s and 2030s advancing by 3–23 d. Future monitoring of airborne olive pollen may therefore provide an early biological indicator of climatic warming in the Mediterranean

Low Speed Automation, a French Initiative

Nowadays, vehicle safety is constantly increasing thanks to the improvement of vehicle passive and active safety. However, on a daily usage of the car, traffic jams remains a problem. With limited space for road infrastructure, automation of the driving task on specific situation seems to be a possible solution. The French project ABV, which stands for low speed automation, tries to demonstrate the feasibility of the concept and to prove the benefits. In this article, we describe the scientific background of the project and expected outputs

Effects of levothyroxine substitution therapy on hunger and food intake in individuals with hypothyroidism

Context: In individuals with hypothyroidism and overweight, levothyroxine substitution therapy is often expected to cause weight loss due to its effect on resting energy expenditure. However, despite levothyroxine-induced enhancement of resting energy expenditure, fat mass loss is rarely seen after levothyroxine substitution therapy. The mechanism behind this conundrum is unknown. Aim: The aim of the study was to assess the effect of levothyroxine t herapy on hunger sensations and ad libitum food intake in individuals with hypothyroidism. Design and setting: Prospective cohort study of 18 newly diagnosed hypothyroid women (thyroid-stimulating hormone (TSH) >10 mU/L). Participants were investigated at diagnosis, after normalization of TSH (<4.0 mU/L), and after 6 months of successful treatment. Eighteen age and body mass index-matched healthy controls were also included. Intervention: Hypothyroid individuals were treated with levothyroxine according to European Thyroid Association guidelines. Main outcomes: Changes in hunger sensation were assessed using visual analog scales (cm) before and during a standardized mixed meal test, and food intake was measured during a subsequent ad libitum meal (g). Results: After 6 months of levothyroxine therapy, mean resting energy expenditure was increased by 144 kcal/day (10%) (P < 0.001). Weight loss was comprised of 0.8 kg fat-free mass while fat mass remained unchanged. Fasting hunger sensation increased from a mean of 4.5 (s.d. 2.2) cm to 5.5 (s.d. 2.2) cm (P = 0.047). The numerical increase in ad libitum meal intake did not reach statistical significance. Conclusion: Our data suggest that levothyroxine-induced hunger may be a culprit in the lack of fat mass loss from levothyroxine therapy

Identifying Schistosoma japonicum Excretory/Secretory Proteins and Their Interactions with Host Immune System

Schistosoma japonicum is a major infectious agent of schistosomiasis. It has been reported that large number of proteins excreted and secreted by S. japonicum during its life cycle are important for its infection and survival in definitive hosts. These proteins can be used as ideal candidates for vaccines or drug targets. In this work, we analyzed the protein sequences of S. japonicum and found that compared with other proteins in S. japonicum, excretory/secretory (ES) proteins are generally longer, more likely to be stable and enzyme, more likely to contain immune-related binding peptides and more likely to be involved in regulation and metabolism processes. Based on the sequence difference between ES and non-ES proteins, we trained a support vector machine (SVM) with much higher accuracy than existing approaches. Using this SVM, we identified 191 new ES proteins in S. japonicum, and further predicted 7 potential interactions between these ES proteins and human immune proteins. Our results are useful to understand the pathogenesis of schistosomiasis and can serve as a new resource for vaccine or drug targets discovery for anti-schistosome

Spatially, Temporally and Polarization-Resolved Photoluminescence Exploration of Excitons in Crystalline Phthalocyanine Thin Films

The lack of long range order in organic semiconductor thin films prevents the unveiling of the complete nature of excitons in optical experiments, because the diffraction limited beam diameters in the bandgap region far exceed typical crystalline grain sizes. Here we present spatially-, temporally- and polarization-resolved dual photoluminescence/linear dichroism microscopy experiments that investigate exciton states within a single crystalline grain in solution-processed phthalocyanine thin films. These experiments reveal the existence of a delocalized singlet exciton, polarized along the high mobility axis in this quasi-1D electronic system. The strong delocalized {\pi} orbitals overlap controlled by the molecular stacking along the high mobility axis is responsible for breaking the radiative recombination selection rules. Using our linear dichroism scanning microscopy setup we further established a rotation of molecules (i.e. a structural phase transition) that occurs above 100 K prevents the observation of this exciton at room temperature.Comment: submitted to Journal of Chem Phys letter